Process for making a detergent composition by non-tower process

ABSTRACT

A non-tower process for continuously preparing granular detergent composition having a density of at least about 600 g/l is provided. The process comprises the steps of (a) dispersing a surfactant, and coating the surfactant with fine powder having a diameter from 0.1 to 500 microns, in a mixer, wherein first agglomerates are formed, (b) thoroughly mixing the first agglomerates in a mixer, wherein second agglomerates are formed, and (c) spraying finely atomized liquid onto the second agglomerates in a mixer.

FIELD OF THE INVENTION

The present invention generally relates to a non-tower process forproducing a particulate detergent composition. More particularly, theinvention is directed to a continuous process during which detergentagglomerates are produced by feeding a surfactant and coating materialsinto a series of mixers. The process produces a free flowing, detergentcomposition whose density can be adjusted for wide range of consumerneeds, and which can be commercially sold.

BACKGROUND OF THE INVENTION

Recently, there has been considerable interest within the detergentindustry for laundry detergents which are “compact” and therefore, havelow dosage volumes. To facilitate production of these so-called lowdosage detergents, many attempts have been made to produce high bulkdensity detergents, for example with a density of 600 g/l or higher. Thelow dosage detergents are currently in high demand as they conserveresources and can be sold in small packages which are more convenientfor consumers. However, the extent to which modem detergent productsneed to be “compact” in nature remains unsettled. In fact, manyconsumers, especially in developing countries, continue to prefer ahigher dosage levels in their respective laundering operations.

Generally, there are two primary types of processes by which detergentgranules or powders can be prepared. The first type of process involvesspray-drying an aqueous detergent slurry in a spray-drying tower toproduce highly porous detergent granules (e.g., tower process for lowdensity detergent compositions). In the second type of process, thevarious detergent components are dry mixed after which they areagglomerated with a binder such as a nonionic or anionic surfactant, toproduce high density detergent compositions (e.g., agglomeration processfor high density detergent compositions). In the above two processes,the important factors which govern the density of the resultingdetergent granules are the shape, porosity and particle sizedistribution of said granules, the density of the various startingmaterials, the shape of the various starting materials, and theirrespective chemical composition.

There have been many attempts in the art for providing processes whichincrease the density of detergent granules or powders. Particularattention has been given to densification of spray-dried granules bypost tower treatment. For example, one attempt involves a batch processin which spray-dried or granulated detergent powders containing sodiumtripolyphosphate and sodium sulfate are densified and spheronized in aMarumerizer®. This apparatus comprises a substantially horizontal,roughened, rotatable table positioned within and at the base of asubstantially vertical, smooth walled cylinder. This process, however,is essentially a batch process and is therefore less suitable for thelarge scale production of detergent powders. More recently, otherattempts have been made to provide continuous processes for increasingthe density of “post-tower” or spray dried detergent granules.Typically, such processes require a first apparatus which pulverizes orgrinds the granules and a second apparatus which increases the densityof the pulverized granules by agglomeration. While these processesachieve the desired increase in density by treating or densifying “posttower” or spray dried granules, they are limited in their ability to gohigher in surfactant active level without subsequent coating step. Inaddition, treating or densifying by “post tower” is not favourable interms of economics (high capital cost) and complexity of operation.Moreover, all of the aforementioned processes are directed primarily fordensifying or otherwise processing spray dried granules. Currently, therelative amounts and types of materials subjected to spray dryingprocesses in the production of detergent granules has been limited. Forexample, it has been difficult to attain high levels of surfactant inthe resulting detergent composition, a feature which facilitatesproduction of detergents in a more efficient manner. Thus, it would bedesirable to have a process by which detergent compositions can beproduced without having the limitations imposed by conventional spraydrying techniques.

To that end, the art is also replete with disclosures of processes whichentail agglomerating detergent compositions. For example, attempts havebeen made to agglomerate detergent builders by mixing zeolite and/orlayered silicates in a mixer to form free flowing agglomerates. Whilesuch attempts suggest that their process can be used to producedetergent agglomerates, they do not provide a mechanism by whichstarting detergent materials in the form of pastes, liquids and drymaterials can be effectively agglomerated into crisp, free flowingdetergent agglomerates.

Accordingly, there remains a need in the art to have an agglomeration(non-tower) process for continuously producing a detergent compositionhaving high density delivered directly from starting detergentingredients, and preferably the density can be achieved by adjusting theprocess condition. Also, there remains a need for such a process whichis more efficient, flexible and economical to facilitate large-scaleproduction of detergents (1) for flexibility in the ultimate density ofthe final composition, and (2) for flexibility in terms of incorporatingseveral different kinds of detergent ingredients (especially liquidingredients) into the process.

The following references are directed to densifying spray-driedgranules: Appel et al, U.S. Pat. No. 5,133,924 (Lever); Bortolotti etal, U.S. Pat. No. 5,160,657 (Lever); Johnson et al, British patent No.1,517,713 (Unilever); and Curtis, European Patent Application 451,894.

The following references are directed to producing detergents byagglomeration: Beujean et al, Laid-open No. WO93/23,523 (Henkel), Lutzet al, U.S. Pat. No. 4,992,079 (FMC Corporation); Porasik et al, U.S.Pat. No. 4,427,417 (Korex); Beerse et al, U.S. Pat. No. 5,108,646(Procter & Gamble), Capeci et al, U.S. Pat. No. 5,366,652 (Procter &Gamble); Hollingsworth et al, European Patent Application 351,937(Unilever); Swatling et al, U.S. Pat. No. 5,205,958; Dhalewadikar et al,Laid Open No. WO96104359 (Unilever).

For example, the Laid-open No. WO93123,523 (Henkel) describes theprocess comprising pre-agglomeration by a low speed mixer and furtheragglomeration step by high speed mixer for obtaining high densitydetergent composition with less than 25 wt % of the granules having adiameter over 2 mm. The U.S. Pat. No. 4,427,417 (Korex) describescontinuous process for agglomeration which reduces caking and oversizedagglomerates.

None of the existing art provides all of the advantages and benefits ofthe present invention.

SUMMARY OF THE INVENTION

The present invention meets the aforementioned needs in the art byproviding a process which produces a high density granular detergentcomposition. The present invention also meets the aforementioned needsin the art by providing a process which produces a granular detergentcomposition for flexibility in the ultimate density of the finalcomposition from agglomeration (e.g., non-tower) process. The processdoes not use the conventional spray drying towers currently which islimited in producing high surfactant loading compositions. In addition,the process of the present invention is more efficient, economical andflexible with regard to the variety of detergent compositions which canbe produced in the process. Moreover, the process is more amenable toenvironmental concerns in that it does not use spray drying towers whichtypically emit particulates and volatile organic compounds into theatmosphere.

As used herein, the term “agglomerates” refers to particles formed byagglomerating raw materials with binder such as surfactants and orinorganic solutions/organic solvents and polymer solutions. As usedherein, the term “mean residence time” refers to following definition:

mean residence time (hr)=mass (kg)/flow throughput (kg/hr)

All percentages used herein are expressed as “percent-by-weight” unlessindicated otherwise. All ratios are weight ratios unless indicatedotherwise. As used herein, “comprising” means that other steps and otheringredients which do not affect the result can be added. This termencompasses the terms “consisting of” and “consisting essentially of”.

In accordance with one aspect of the invention, a process for preparinga granular detergent composition having a density at least about 600 g/lis provided.

The process comprises the steps of:

(a) dispersing a surfactant, and coating the surfactant with fine powderhaving a diameter from 0.1 to 500 microns, in a mixer wherein conditionsof the mixer include (i) from about 2 to about 50 seconds of meanresidence time, (ii) from about 4 to about 25 m/s of tip speed, and(iii) from about 0.15 to about 7 kj/kg of energy condition, whereinfirst agglomerates are formed;

(b) thoroughly mixing the first agglomerates in a mixer whereinconditions of the mixer include (i) from about 0.5 to about 15 minutesof mean residence time and (ii) from about 0.15 to about 7 kj/kg ofenergy condition, wherein second agglomerates are formed; and

(c) spraying finely atomized liquid onto the second agglomerates in amixer wherein conditions of the mixer include (i) from about 0.2 toabout 5 seconds of mean residence time, (ii) from about 10 to about 30m/s of tip speed, and (iii) from about 0.15 to about 5 kj/kg of energycondition.

Also provided are the granular detergent compositions having a highdensity of at least about 600 g/l, produced by any one of the processembodiments described herein.

Accordingly, it is an object of the invention to provide a process forcontinuously producing a detergent composition which has flexibilitywith respect to density of the final products by controlling energyinput, residence time condition, and tip speed condition in the mixers.It is also an object of the invention to provide a process which is moreefficient, flexible and economical to facilitate large-scale production.These and other objects, features and attendant advantages of thepresent invention will become apparent to those skilled in the art froma reading of the following detailed description of the preferredembodiment and the appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention is directed to a process which produces freeflowing, granular detergent agglomerates having a density of at leastabout 600 g/l. The process produces granular detergent agglomerates froman aqueous and/or non-aqueous surfactant which is then coated with finepowder having a diameter from 0.1 to 500 microns, in order to obtain lowdensity granules.

Process

First Step [Step (a)]

In the first step of the process, one or more of aqueous and/ornon-aqueous surfactant(s), which is/are in the form of powder, pasteand/or liquid, and fine powder having a diameter from 0.1 to 500microns, preferably from about 1 to about 100 microns are fed into afirst mixer, so as to make agglomerates. (The definition of thesurfactants and the fine powder are described in detail hereinafter.)Optionally, an internal recycle stream of powder, generally having adiameter of about 0.1 to about 300 microns, which can be generated froman “optional conditioning process (i.e., drying and/or cooling step),”which is an additional step after the process of present invention canbe fed into the mixer in addition to the fine powder. The amount of suchinternal recycle stream of powder can be 0 to about 60 wt % of finalproduct.

In another embodiment of the invention, the surfactant(s) can beinitially fed into a mixer or pre-mixer (e.g. a conventional screwextruder or other similar mixer) prior to the above, after which themixed detergent materials are fed into the first step mixer as describedherein for agglomeration.

Generally speaking, preferably, the mean residence time of the firstmixer is in range from about 2 to about 50 seconds and tip speed of thefirst mixer is in range from about 4 m/s to about 25 m/s, the energy perunit mass of the first mixer (energy condition) is in range from about0.15 kj/kg to about 7 kj/kg, more preferably, the mean residence time ofthe first mixer is from about 5 to about 30 seconds and tip speed of thefirst mixer is in range from about 6 m/s to about 18 m/s, the energy perunit mass of the first mixer (energy condition) is in range from about0.3 kj/kg to about 4 kj/kg, and most preferably, the mean residence timein the first mixer is in range from about 5 to about 20 seconds and tipspeed of the first mixer is in range from about 8 m/s to about 18 m/s,the energy per unit mass of the first mixer (energy condition) is inrange from about 0.3 kj/kg to about 4 kj/kg.

The examples of mixers for the first step can be any types of mixerknown to the skilled in the art, as long as the mixer can maintain theabove mentioned condition for the first step. An Example can be LödigeCB Mixer manufactured by the Lödige company (Germany). As the result ofthe first step, agglomerates having fine powder on the surface of theagglomerates (first agglomerates) are then obtained.

Second Step [Step (b)]

The first agglomerates are fed into a second mixer agglomeration.Namely, the resultant product from the first mixer is mixed and shearedthoroughly for rounding and growth of the agglomerates in the secondmixer. Optionally, about 0-10% , more preferably about 2-5% of powderdetergent ingredients of the kind used in the first step and/or otherdetergent ingredients can be added to the second step. Preferably,choppers which are attachable for the second mixer can be used to breakup undesirable oversized agglomerates. Therefore, the process includingthe second mixer with choppers is useful in order to obtain reducedamount of oversized agglomerates as final products, and such process isone preferred embodiment of the present invention.

Generally speaking, preferably, the mean residence time of the secondmixer is in the range from about 0.5 to about 15 minutes and the energyper unit mass of the second mixer (energy condition) is in the rangefrom about 0.15 to about 7 kj/kg, more preferably, the mean residencetime of the second mixer is in the range from about 3 to about 6 minutesand the energy per unit mass of the second mixer (energy condition) isin the range from about 0.15 to about 4kj/kg.

The examples of the second mixer can be any types of mixer known to theskilled in the art, as long as the mixer can maintain the abovementioned condition for the first step. An Example can be Lödige KMMixer manufactured by the Lödige company (Germany).

Third Step (Step c)

The agglomerates from the second step, the second agglomerates, are fedinto a third mixer. Finely atomized liquid is sprayed on theagglomerates in the third mixer. If excessive fine powder from the firstand/or the second step is optionally added to the step, spraying thefinely atomized liquid is useful in order to bind the excessive finepowder onto the second agglomerates. About 0-10%, more preferably about2-5% of powder detergent ingredients of the kind used in the first step,the second step, and/or other detergent ingredients can be added to thesecond mixer.

Generally speaking, preferably, the mean residence time of the thirdmixer is in range from about 0.2 to about 5 seconds and tip speed of thethird mixer is in range from about 10 m/s to about 30 m/s, the energyper unit mass of the third mixer (energy condition) is in range fromabout 0.15 kj/kg to about 5 kj/kg, more preferably, the mean residencetime of the third mixer is in range from about 0.2 to about 5 secondsand tip speed for the third mixer is in range from about 10 m/s to about30 m/s, the energy per unit mass of the third mixer (energy condition)is in range from about 0.15 kj/kg to about 5 kj/kg, the most preferably,the mean residence time of the third mixer is in range from about 0.2 toabout 5 seconds, tip speed for the third mixer is in range from about 15m/s to about 26 m/s, the energy per unit mass of the third mixer (energycondition) is in range from about 0.15 kj/kg to about 2 kj/kg.

The examples of the third mixer can be any types of mixer known to theskilled in the art, as long as the mixer can maintain the abovementioned condition for the third step. An Example can be Flexomic Modelmanufactured by the Schugi company (Netherlands). As the result of thethird step, a further agglomerated resultant, having a density of atleast 600 g/l is then obtained. Optionally, the resultant can be furthersubjected to drying, cooling and/or grinding.

In the case that the process of the present invention is proceeded byusing (1) CB mixer which has flexibility to inject at least two liquidingredients,(2) KM mixer which has flexibility to inject at least aliquid ingredient, (3) Schugi Mixer which has flexibility to inject atleast two liquid ingredients, the process can incorporate five differentkinds of liquid ingredients in the process. Therefore, the proposedprocess is beneficial for the skilled in the art in order to incorporatestarting detergent materials which is in the form of liquid, which israther expensive and sometimes more difficult in terms of handlingand/or storage than solid materials, for into a granular making process.

Starting Detergent Materials

The total amount of the surfactants in products made by the presentinvention, which are included in the following detergent materials,finely atomized liquid and adjunct detergent ingredients, is generallyfrom about 5% to about 60%, more preferably from about 12% to about 40%,more preferably, from about 15 to about 35%, in total amount of thefinal product obtained by the process of the present invention. Thesurfactants which should be included in the above can be from any partof the process of the present invention., e.g., from either one of thefirst step, the second step and/or the third step of the presentinvention.

Detergent Surfactant (Aqueous/Non-aqueous)

The amount of the surfactant of the present process can be from about 5%to about 60%, more preferably from about 12% to about 40%, morepreferably, from about 15 to about 35%, in total amount of the finalproduct obtained by the process of the present invention.

The surfactant of the present process, which is used as the abovementioned starting detergent materials in the first step, is in the formof powdered, pasted or liquid raw materials.

The surfactant itself is preferably selected from anionic, nonionic,zwitterionic, ampholytic and cationic classes and compatible mixturesthereof. Detergent surfactants useful herein are described in U.S. Pat.No. 3,664,961, Norris, issued May 23, 1972, and in U.S. Pat. No.3,929,678, Laughlin et al., issued Dec. 30, 1975, both of which areincorporated herein by reference. Useful cationic surfactants alsoinclude those described in U.S. Pat. 4,222,905, Cockrell, issued Sep.16, 1980, and in U.S. Pat. No. 4,239,659, Murphy, issued Dec. 16, 1980,both of which are also incorporated herein by reference. Of thesurfactants, anionics and nonionics are preferred and anionics are mostpreferred.

Nonlimiting examples of the preferred anionic surfactants useful in thepresent invention include the conventional C₁₁-C₁₈ alkyl benzenesulfonates (“LAS”), primary, branched-chain and random C₁₀-C₂₀ alkylsulfates (“AS”), the C₁₀-C₁₈ secondary (2,3) alkyl sulfates of theformula CH₃(CH₂)_(x)(CHOSO₃ ⁻M⁺) CH₃ and CH₃ (CH₂)_(y)(CHOSO₃ ⁻M⁺)CH₂CH₃ where x and (y+1) are integers of at least about 7, preferably atleast about 9, and M is a water-solubilizing cation, especially sodium,unsaturated sulfates such as oleyl sulfate, and the C₁₀-C₁₈ alkyl alkoxysulfates (“AE_(x)S”; especially EO 1-7 ethoxy sulfates).

Useful anionic surfactants also include water-soluble salts of2-acyloxyalkane-1-sulfonic acids containing from about 2 to 9 carbonatoms in the acyl group and from about 9 to about 23 carbon atoms in thealkane moiety; water-soluble salts of olefin sulfonates containing fromabout 12 to 24 carbon atoms; and beta-alkyloxy alkane sulfonatescontaining from about 1 to 3 carbon atoms in the alkyl group and fromabout 8 to 20 carbon atoms in the alkane moiety.

Optionally, other exemplary surfactants useful in the invention includeC₁₀-C₁₈ alkyl alkoxy carboxylates (especially the EO 1-5ethoxycarboxylates), the C₁₀-C₁₈ glycerol ethers, the C₁₀-C₁₈ alkylpolyglycosides and the corresponding sulfated polyglycosides, andC₁₂-C₁₈ alpha-sulfonated fatty acid esters. If desired, the conventionalnonionic and amphoteric surfactants such as the C₁₂-C₁₈ alkylethoxylates (“AE”) including the so-called narrow peaked alkylethoxylates and C₆-C₁₂ alkyl phenol alkoxylates (especially ethoxylatesand mixed ethoxy/propoxy), C₁₀-C₁₈ amine oxides, and the like, can alsobe included in the overall compositions. The C₁₀-C₁₈ N-alkyl polyhydroxyfatty acid amides can also be used. Typical examples include the C₁-C₁₈N-methylglucamides. See WO 9,206,154. Other sugar-derived surfactantsinclude the N-alkoxy polyhydroxy fatty acid amides, such as C₁₀-C₁₈N-(3-methoxypropyl) glucamide. The N-propyl through N-hexyl C₁₂-C₁₈glucamides can be used for low sudsing. C₁₀-C₂₀ conventional soaps mayalso be used. If high sudsing is desired, the branched-chain C₁₀-C₁₆soaps may be used. Mixtures of anionic and nonionic surfactants areespecially useful. Other conventional useful surfactants are listed instandard texts.

Cationic surfactants can also be used as a detergent surfactant hereinand suitable quaternary ammonium surfactants are selected from monoC₆-C₁₆, preferably C₆-C₁₀ N-alkyl or alkenyl ammonium surfactantswherein remaining N positions are substituted by methyl, hydroxyethyl orhydroxypropyl groups.

Ampholytic surfactants can also be used as a detergent surfactantherein, which include aliphatic derivatives of heterocyclic secondaryand tertiary amines; zwitterionic surfactants which include derivativesof aliphatic quaternary ammonium, phosphonium and sulfonium compounds;water-soluble salts of esters of alpha-sulfonated fatty acids; alkylether sulfates; water-soluble salts of olefin sulfonates; beta-alkyloxyalkane sulfonates; betaines having the formula R(R¹)₂N⁺R²COO—, wherein Ris a C₆-C₁₈ hydrocarbyl group, preferably a C₁₀-C₁₆ alkyl group orC₁₀-C₁₆ acylamido alkyl group, each R¹ is typically C₁-C₃ alkyl,preferably methyl and R₂ is a C₁-C₅ hydrocarbyl group, preferably aC₁-C₃ alkylene group, more preferably a C₁-C₂ alkylene group. Examplesof suitable betaines include coconut acylamidopropyldimethyl betaine;hexadecyl dimethyl betaine; C₁₂₋₁₄ acylamidopropylbetaine; C₈₋₁₄acylamidohexyldiethyl betaine; 4[C₁₄₋₁₆acylmethylamidodiethylammonio]-1-carboxybutane; C₁₆₋₁₈acylamidodimethylbetaine; C₁₂₋₁₆ acylamidopentanediethylbetaine; and[C₁₂₋₁₆ acylmethylamidodimethylbetaine. Preferred betaines are C₁₂₋₁₈dimethyl-ammonio hexanoate and the C₁₀₋₁₈ acylamidopropane (or ethane)dimethyl (or diethyl) betaines; and the sultaines having the formula(R(R¹)₂N⁺R²SO₃ ⁻ wherein R is a C₆-C₁₈ hydrocarbyl group, preferably aC₁₀-C₁₆ alkyl group, more preferably a C₁₂-C₁₃ alkyl group, each R¹ istypically C₁-C₃ alkyl, preferably methyl, and R² is a C₁-C₆ hydrocarbylgroup, preferably a C₁-C₃ alkylene or, preferably, hydroxyalkylenegroup. Examples of suitable sultaines include C₁₂-C₁₄dimethylammonio-2-hydroxypropyl sulfonate, C₁₂-C₁₄ amido propylammonio-2-hydroxypropyl sultaine, C₁₂-C₁₄ dihydroxyethylammonio propanesulfonate, and C₁₆₋₁₈ dimethylammonio hexane sulfonate, with C₁₂₋₁₄amido propyl ammonio-2-hydroxypropyl sultaine being preferred.

Fine Powder

The amount of the fine powder of the present process, which is used inthe first step, can be from about 94% to 30%, preferably from 86% to54%, in total amount of starting material for the first step . Thestarting fine powder of the present process preferably selected from thegroup consisting of ground soda ash, powdered sodium tripolyphosphate(STPP), hydrated tripolyphosphate, ground sodium sulphates,aluminosilicates, crystalline layered silicates, nitrilotriacetates(NTA), phosphates, precipitated silicates, polymers, carbonates,citrates, powdered surfactants (such as powdered alkane sulfonic acids)and internal recycle stream of powder occurring from the process of thepresent invention, wherein the average diameter of the powder is from0.1 to 500 microns, preferably from 1 to 300 microns, more preferablyfrom 5 to 100 microns. In the case of using hydrated STPP as the finepowder of the present invention, STPP which is hydrated to a level ofnot less than 50% is preferable. The aluminosilicate ion exchangematerials used herein as a detergent builder preferably have both a highcalcium ion exchange capacity and a high exchange rate. Withoutintending to be limited by theory, it is believed that such high calciumion exchange rate and capacity are a function of several interrelatedfactors which derive from the method by which the aluminosilicate ionexchange material is produced. In that regard, the aluminosilicate ionexchange materials used herein are preferably produced in accordancewith Corkill et al, U.S. Pat. No. 4,605,509 (Procter & Gamble), thedisclosure of which is incorporated herein by reference.

Preferably, the aluminosilicate ion exchange material is in “sodium”form since the potassium and hydrogen forms of the instantaluminosilicate do not exhibit as high of an exchange rate and capacityas provided by the sodium form. Additionally, the aluminosilicate ionexchange material preferably is in over dried form so as to facilitateproduction of crisp detergent agglomerates as described herein. Thealuminosilicate ion exchange materials used herein preferably haveparticle size diameters which optimize their effectiveness as detergentbuilders. The term “particle size diameter” as used herein representsthe average particle size diameter of a given aluminosilicate ionexchange material as determined by conventional analytical techniques,such as microscopic determination and scanning electron microscope(SEM). The preferred particle size diameter of the aluminosilicate isfrom about 0.1 micron to about 10 microns, more preferably from about0.5 microns to about 9 microns. Most preferably, the particle sizediameter is from about 1 microns to about 8 microns.

Preferably, the aluminosilicate ion exchange material has the formula

Na_(z)[(AlO₂)_(z).(SiO₂)_(y)]xH₂O

wherein z and y are integers of at least 6, the molar ratio of z to y isfrom about 1 to about 5 and x is from about 10 to about 264. Morepreferably, the aluminosilicate has the formula

Na₁₂[(AlO₂)₁₂.(SiO₂)₁₂]xH₂O

wherein x is from about 20 to about 30, preferably about 27. Thesepreferred aluminosilicates are available commercially, for example underdesignations Zeolite A, Zeolite B and Zeolite X. Alternatively,naturally-occurring or synthetically derived aluminosilicate ionexchange materials suitable for use herein can be made as described inKrummel et al, U.S. Pat. No. 3,985,669, the disclosure of which isincorporated herein by reference.

The aluminosilicates used herein are further characterized by their ionexchange capacity which is at least about 200 mg equivalent of CaCO₃hardness/gram, calculated on an anhydrous basis, and which is preferablyin a range from about 300 to 352 mg equivalent of CaCO₃ hardness/gram.Additionally, the instant aluminosilicate ion exchange materials arestill further characterized by their calcium ion exchange rate which isat least about 2 grains Ca⁺⁺/gallon/minute/-gram/gallon, and morepreferably in a range from about 2 grainsCa⁺⁺/gallon/minutel-gram/gallon to about 6 grainsCa⁺⁺/gallon/minute/gram/gallon.

Finely Atomized Liquid

The amount of the finely atomized liquid of the present process can befrom about 1% to about 10% (active basis), preferably from 2% to about6% (active basis) in total amount of the final product obtained by theprocess of the present invention. The finely atomized liquid of thepresent process can be selected from the group consisting of liquidsilicate, anionic or cationic surfactants which are in liquid form,aqueous or non-aqueous polymer solutions, water and mixtures thereof.Other optional examples for the finely atomized liquid of the presentinvention can be sodium carboxy methyl cellulose solution, polyethyleneglycol (PEG), and solutions of dimethylene triamine pentamethylphosphonic acid (DETMP),

The preferable examples of the anionic surfactant solutions which can beused as the finely atomized liquid in the present inventions are about88-97% active HLAS, about 30-50% active NaLAS, about 28% active AE3Ssolution, about 40-50% active liquid silicate, and so on.

Cationic surfactants can also be used as finely atomized liquid hereinand suitable quaternary ammonium surfactants are selected from monoC₆-C₁₆, preferably C₆-C₁₀ N-alkyl or alkenyl ammonium surfactantswherein remaining N positions are substituted by methyl, hydroxyethyl orhydroxypropyl groups.

Preferable examples of the aqueous or non-aqueous polymer solutionswhich can be used as the finely atomized liquid in the presentinventions are modified polyamines which comprise a polyamine backbonecorresponding to the formula:

having a modified polyamine formula V_((n+1))W_(m)Y_(n)Z or a polyaminebackbone corresponding to the formula:

having a modified polyamine formula V_((n−k+1))W_(m)Y_(n)Y′_(k)Z,wherein k is less than or equal to n, said polyamine backbone prior tomodification has a molecular weight greater than about 200 daltons,wherein

i) V units are terminal units having the formula:

ii) W units are backbone units having the formula:

iii) Y units are branching units having the formula:

iv) Z units are terminal units having the formula:

wherein backbone linking R units are selected from the group consistingof C₂-C₁₂ alkylene, C₄-C₁₂ alkenylene, C₃-C₁₂ hydroxyalkylene, C₄-C₁₂dihydroxy-alkylene, C₈-C₁₂ dialkylarylene, —(R¹O)_(x)R¹—,—(R¹O)_(x)R⁵(OR¹)_(x)—,—(CH₂CH(OR²)CH₂O)_(z)(R¹O)_(y)R¹(OCH₂CH(OR²)CH₂)_(w)—,—C(O)(R⁴)_(r)C(O)—, —CH₂CH(OR²)CH₂—, and mixtures thereof; wherein R¹ isC₂-C₆ alkylene and mixtures thereof; R² is hydrogen, —(R¹O)_(x)B, andmixtures thereof; R³ is C₁-C₁₈ alkyl, C₇-C₁₂ arylalkyl, C₇-C₁₂ alkylsubstituted aryl, C₆-C₁₂ aryl, and mixtures thereof; R⁴ is C₁-C₁₂alkylene, C₄-C₁₂ alkenylene, C₈-C₁₂ arylalkylene, C₆-C₁₀ arylene, andmixtures thereof; R⁵ is C₁-C₁₂ alkylene, C₃-C₁₂ hydroxyalkylene, C₄-C₁₂dihydroxy-alkylene, C₈-C₁₂ dialkylarylene, —C(O)—, —C(O)NHR⁶NHC(O)—,—R¹(OR¹)—, —C(O)(R⁴)_(r)C(O)—, —CH₂CH(OH)CH₂—,—CH₂CH(OH)CH₂O(R¹O)_(y)R¹OCH₂CH(OH)CH₂—, and mixtures thereof; R⁶ isC₂-C₁₂ alkylene or C₆-C₁₂ arylene; E units are selected from the groupconsisting of hydrogen, C₁-C₂₂ alkyl, C₃-C₂₂ alkenyl, C₇-C₂₂ arylalkyl,C₂-C₂₂ hydroxyalkyl, —(CH₂)_(p)CO₂M, —(CH₂)_(q)SO₃M, —CH(CH₂CO₂M)CO₂M,—(CH₂)_(p)PO₃M, —(R¹O)_(x)B, —C(O)R³, and mixtures thereof; oxide; B ishydrogen, C₁-C₆ alkyl, —(CH₂)_(q)SO₃M, —(CH₂)_(p)CO₂M,—(CH₂)_(q)(CHSO₃M)CH₂SO₃M, —(CH₂)_(q)—(CHSO₂M)CH₂SO₃M, —(CH₂)_(p)PO₃M,—PO₃M, and mixtures thereof; M is hydrogen or a water soluble cation insufficient amount to satisfy charge balance; X is a water soluble anion;m has the value from 4 to about 400; n has the value from 0 to about200; p has the value from 1 to 6, q has the value from 0 to 6; r has thevalue of 0 or 1; w has the value 0 or 1; x has the value from 1 to 100;y has the value from 0 to 100; z has the value 0 or 1. One example ofthe most preferred polyethyleneimines would be a polyethyleneiminehaving a molecular weight of 1800 which is further modified byethoxylation to a degree of approximately 7 ethyleneoxy residues pernitrogen (PEI 1800, E7). It is preferable for the above polymer solutionto be pre-complex with anionic surfactant such as NaLAS.

Other preferable examples of the aqueous or non-aqueous polymersolutions which can be used as the finely atomized liquid in the presentinvention are polymeric polycarboxylate dispersants which can beprepared by polymerizing or copolymerizing suitable unsaturatedmonomers, preferably in their acid form. Unsaturated monomeric acidsthat can be polymerized to form suitable polymeric polycarboxylatesinclude acrylic acid, maleic acid (or maleic anhydride), fumaric acid,itaconic acid, aconitic acid, mesaconic acid, citraconic acid andmethylenemalonic acid. The presence in the polymeric polycarboxylatesherein of monomeric segments, containing no carboxylate radicals such asvinylmethyl ether, styrene, ethylene, etc. is suitable provided thatsuch segments do not constitute more than about 40% by weight of thepolymer.

Homo-polymeric polycarboxylates which have molecular weights above 4000,such as described next are preferred. Particularly suitablehomo-polymeric polycarboxylates can be derived from acrylic acid. Suchacrylic acid-based polymers which are useful herein are thewater-soluble salts of polymerized acrylic acid. The average molecularweight of such polymers in the acid form preferably ranges from above4,000 to 10,000, preferably from above 4,000 to 7,000, and mostpreferably from above 4,000 to 5,000. Water-soluble salts of suchacrylic acid polymers can include, for example, the alkali metal,ammonium and substituted ammonium salts.

Co-polymeric polycarboxylates such as a Acrylic/maleic-based copolymersmay also be used. Such materials include the water-soluble salts ofcopolymers of acrylic acid and maleic acid. The average molecular weightof such copolymers in the acid form preferably ranges from about 2,000to 100,000, more preferably from about 5,000 to 75,000, most preferablyfrom about 7,000 to 65,000. The ratio of acrylate to maleate segments insuch copolymers will generally range from about 30:1 to about 1:1, morepreferably from about 10:1 to 2:1. Water-soluble salts of such acrylicacid/maleic acid copolymers can include, for example, the alkali metal,ammonium and substituted ammonium salts. It is preferable for the abovepolymer solution to be pre-complexed with anionic surfactant such asLAS.

Adjunct Detergent Ingredients

The starting detergent material in the present process can includeadditional detergent ingredients and/or, any number of additionalingredients can be incorporated in the detergent composition duringsubsequent steps of the present process. These adjunct ingredientsinclude other detergency builders, bleaches, bleach activators, sudsboosters or suds suppressors, anti-tarnish and anticorrosion agents,soil suspending agents, soil release agents, germicides, pH adjustingagents, non-builder alkalinity sources, chelating agents, smectiteclays, enzymes, enzyme-stabilizing agents and perfumes. See U.S. Pat.No. 3,936,537, issued Feb. 3, 1976 to Baskerville, Jr. et al.,incorporated herein by reference.

Other builders can be generally selected from the various water-soluble,alkali metal, ammonium or substituted ammonium phosphates,polyphosphates, phosphonates, polyphosphonates, carbonates, borates,polyhydroxy sulfonates, polyacetates, carboxylates, andpolycarboxylates. Preferred are the alkali metal, especially sodium,salts of the above. Preferred for use herein are the phosphates,carbonates, C₁₀₋₁₈ fatty acids, polycarboxylates, and mixtures thereof.More preferred are sodium tripolyphosphate, tetrasodium pyrophosphate,citrate, tartrate mono- and di-succinates, and mixtures thereof (seebelow).

In comparison with amorphous sodium silicates, crystalline layeredsodium silicates exhibit a clearly increased calcium and magnesium ionexchange capacity. In addition, the layered sodium silicates prefermagnesium ions over calcium ions, a feature necessary to insure thatsubstantially all of the “hardness” is removed from the wash water.These crystalline layered sodium silicates, however, are generally moreexpensive than amorphous silicates as well as other builders.Accordingly, in order to provide an economically feasible laundrydetergent, the proportion of crystalline layered sodium silicates usedmust be determined judiciously. Such crystalline layered sodiumsilicates are discussed in Corkill et al, U.S. Pat. No. 4,605,509,previously incorporated herein by reference.

Specific examples of inorganic phosphate builders are sodium andpotassium tripolyphosphate, pyrophosphate, polymeric metaphosphatehaving a degree of polymerization of from about 6 to 21, andorthophosphates. Examples of polyphosphonate builders are the sodium andpotassium salts of ethylene diphosphonic acid, the sodium and potassiumsalts of ethane 1-hydroxy-1, 1-diphosphonic acid and the sodium andpotassium salts of ethane, 1,1,2-triphosphonic acid. Other phosphorusbuilder compounds are disclosed in U.S. Pat. Nos. 3,159,581; 3,213,030;3,422,021; 3,422,137; 3,400,176 and 3,400,148, all of which areincorporated herein by reference.

Examples of nonphosphorus, inorganic builders are tetraboratedecahydrate and silicates having a weight ratio of SiO₂ to alkali metaloxide of from about 0.5 to about 4.0, preferably from about 1.0 to about2.4. Water-soluble, nonphosphorus organic builders useful herein includethe various alkali metal, ammonium and substituted ammoniumpolyacetates, carboxylates, polycarboxylates and polyhydroxy sulfonates.Examples of polyacetate and polycarboxylate builders are the sodium,potassium, lithium, ammonium and substituted ammonium salts of ethylenediamine tetraacetic acid, nitrilotriacetic acid, oxydisuccinic acid,mellitic acid, benzene polycarboxylic acids, and citric acid.

Polymeric polycarboxylate builders are set forth in U.S. Pat. No.3,308,067, Diehl, issued Mar. 7, 1967, the disclosure of which isincorporated herein by reference. Such materials include thewater-soluble salts of homo- and copolymers of aliphatic carboxylicacids such as maleic acid, itaconic acid, mesaconic acid, fumaric acid,aconitic acid, citraconic acid and methylene malonic acid. Some of thesematerials are useful as the water-soluble anionic polymer as hereinafterdescribed, but only if in intimate admixture with the non-soap anionicsurfactant.

Other suitable polycarboxylates for use herein are the polyacetalcarboxylates described in U.S. Pat. No. 4,144,226, issued Mar. 13, 1979to Crutchfield et al, and U.S. Pat. No. 4,246,495, issued Mar. 27, 1979to Crutchfield et al, both of which are incorporated herein byreference. These polyacetal carboxylates can be prepared by bringingtogether under polymerization condition an ester of glyoxylic acid and apolymerization initiator, The resulting polyacetal carboxylate ester isthen attached to chemically stable end groups to stabilize thepolyacetal carboxylate against rapid depolymerization in alkalinesolution, converted to the corresponding salt, and added to a detergentcomposition. Particularly preferred polycarboxylate builders are theether carboxylate builder compositions comprising a combination oftartrate monosuccinate and tartrate disuccinate described in U.S. Pat.No. 4,663,071, Bush et al., issued May 5, 1987, the disclosure of whichis incorporated herein by reference.

Bleaching agents and activators are described in U.S. Pat. No.4,412,934, Chung et al., issued Nov. 1, 1983, and in U.S. Pat. No.4,483,781, Hartman, issued Nov. 20, 1984, both of which are incorporatedherein by reference. Chelating agents are also described in U.S. Pat.No. 4,663,071, Bush et al., from Column 17, line 54 through Column 18,line 68, incorporated herein by reference. Suds modifiers are alsooptional ingredients and are described in U.S. Pat. Nos. 3,933,672,issued Jan. 20, 1976 to Bartoletta et al., and 4,136,045, issued Jan.23, 1979 to Gault et al., both incorporated herein by reference.

Suitable smectite clays for use herein are described in U.S. Pat.4,762,645, Tucker et al, issued Aug. 9, 1988, Column 6, line 3 throughColumn 7, line 24, incorporated herein by reference. Suitable additionaldetergency builders for use herein are enumerated in the Baskervillepatent, Column 13, line 54 through Column 16, line 16, and in U.S. Pat.No. 4,663,071, Bush et al, issued May 5, 1987, both incorporated hereinby reference.

Optional Process Steps

Optionally, the process can comprise the step of spraying an additionalbinder in one or more than one of the first, second and/or the thirdmixers for the present invention. A binder is added for purposes ofenhancing agglomeration by providing a “binding” or “sticking” agent forthe detergent components. The binder is preferably selected from thegroup consisting of water, anionic surfactants, nonionic surfactants,liquid silicates, polyethylene glycol, polyvinyl pyrrolidonepolyacrylates, citric acid and mixtures thereof. Other suitable bindermaterials including those listed herein are described in Beerse et al,U.S. Pat. No. 5,108,646 (Procter & Gamble Co.), the disclosure of whichis incorporated herein by reference.

Other optional steps contemplated by the present process includescreening the oversized detergent agglomerates in a screening apparatuswhich can take a variety of forms including but not limited toconventional screens chosen for the desired particle size of thefinished detergent product. Other optional steps include conditioning ofthe detergent agglomerates by subjecting the agglomerates to additionaldrying by way of apparatus discussed previously.

Another optional step in the process entails finishing the resultingdetergent agglomerates by a variety of processes including sprayingand/or admixing other conventional detergent ingredients. For example,the finishing step encompasses spraying perfumes, brighteners andenzymes onto the finished agglomerates to provide a more completedetergent composition. Such techniques and ingredients are well known inthe art.

Another optional step in the process involves surfactant pastestructuring process, e.g., hardening an aqueous anionic surfactant pasteby incorporating a paste-hardening material by using an extruder, priorto the process of the present invention. The details of the surfactantpaste structuring process is disclosed in co-application No.PCT/US96115960 (filed Oct. 4, 1996) now WO 98/14550.

In order to make the present invention more readily understood,reference is made to the following examples, which are intended to beillustrative only and not intended to be limiting in scope.

EXAMPLES Example 1

The following is an example for obtaining agglomerates having highdensity, using Lödige CB mixer (CB-30), followed by Lödige KM mixer(KM-600), then Schugi FX-160 Mixer.

[Step 1] 250-270 kg/hr of aqueous coconut fatty alcohol sulfatesurfactant paste (C₁₂-C₁₈, 71.5% active) is dispersed by the pin toolsof a CB-30 mixer along with 220 kg/hr of powdered STPP (mean particlesize of 40-75 microns), 160-200 kg/hr of ground soda ash (mean particlesize of 15 microns), 80-120 kg/hr of ground sodium sulfate (meanparticle size of 15 microns), and the 200 kg/hr of internal recyclestream of powder. The surfactant paste is fed at about 40 to 52° C., andthe powders are fed at room temperature. The condition of the CB-30mixer is as follows:

Mean residence time: 10-18 seconds

Tip speed: 7.5-14 m/s

Energy condition: 0.5-4 kj/kg

Mixer speed: 550-900 rpm

Jacket temperature: 30° C.

[ Step 2] The agglomerates from the CB-30 mixer are fed to the KM-600mixer for further agglomeration, for rounding and growth ofagglomerates. 0-60 kg/hr of ground soda ash (mean particle size of 15microns), or 0-30 kg/hr of Zeolite can be also added in the KM mixer.Choppers for the KM mixer can be used to reduce the amount of oversizedagglomerates. The condition of the KM mixer is as follows:

Mean residence time: 3-6 minutes

Energy condition: 0.15-2 kj/kg

Mixer speed: 100-150 rpm

Jacket temperature: 30-40° C.

[Step 3] The agglomerates from the KM mixer are fed to the Schugi FX-160mixer. 30 kg/hr of HLAS (an acid precursor of C₁₁-C₁₈ alkyl benzenesulfonate; 95% active) is dispersed as finely atomized liquid in theSchugi mixer at about 50 to 60° C. 20-80 kg/hr of soda ash is added inthe Schugi mixer. The condition of the Schugi mixer is as follows:

Mean residence time: 0.2-5 seconds

Tip speed: 16-26 m/s

Energy condition: 0.15-2 kj/kg

Mixer speed: 2000-3200 rpm

The resulting granules from the step 3 have a density of about 700 g/l,and can be optionally subjected to the optional process of cooling,drying, sizing an/or grinding.

Example 2

The following is an example for obtaining agglomerates having highdensity, using Lödige CB mixer (CB-30), followed by Lödige KM mixer(KM-600), then Schugi FX-160 Mixer.

[Step 1] 15 kg/hr—30 kg/hr of HLAS (an acid precursor of C₁₁-C₁₈ alkylbenzene sulfonate; 95% active) at about 50° C., and 250-270 kg/hr ofaqueous CFAS (coconut fatty alcohol sulfate surfactant) paste (C₁₂-C₁₈,70% active) is dispersed by the pin tools of a CB-30 mixer along with220 kg/hr of powdered STPP (mean particle size of 40-75 microns),160-200 kg/hr of ground soda ash (mean particle size of 15 microns),80-120 kg/hr of ground sodium sulfate (mean particle size of 15microns), and the 200 kg/hr of internal recycle stream of powder. Thesurfactant paste is fed at about 45 to 52° C., and the powders are fedat room temperature. The condition of the CB-30 mixer is as follows:

Mean residence time: 10-18 seconds

Tip speed: 7.56-14 m/s

Energy condition: 0.5-4 kj/kg

Mixer speed: 550-900 rpm

Jacket temperature: 30° C.

[Step 2] The agglomerates from the CB-30 mixer are fed to the KM-600mixer for further agglomeration, rounding and growth of agglomerates. 60kg/hr of ground soda ash (mean particle size of 15 microns) is alsoadded in the KM mixer. Serrated plows are used as mixing elements in theKM mixer. Choppers for the KM mixer can be used to reduce the amount ofoversized agglomerates. The condition of the KM mixer is as follows:

Mean residence time: 3-6 minutes

Energy condition : 0.15-2 kj/kg

Mixer speed:100-150 rpm

Jacket temperature: 30-40° C.

[Step 3] The agglomerates from the KM-600 mixer are fed to the SchugiFX-160 mixer. 35 kg/hr of neutralized AE₃S liquid (28% active) isdispersed as finely atomized liquid in the Schugi mixer at about 30-40°C. 20-80 kg/hr of soda ash is added in the Schugi mixer. The conditionof the Schugi mixer is as follows:

Mean residence time: 0.2-5 seconds

Tip speed: 16-26 m/s

Energy condition: 0.15-2 kj/kg

Mixer speed: 2000-3200 rpm

The resulting granules from the step 3 have a density of about 700 g/l,and can be optionally subjected to the optional process of cooling,drying, sizing an/or grinding.

Having thus described the invention in detail, it will be obvious tothose skilled in the art that various changes may be made withoutdeparting from the scope of the invention and the invention is not to beconsidered limited to what is described in the specification.

What is claimed is:
 1. A non-tower process for preparing a granulardetergent composition having a density of at least about 600 g/l,consisting of the steps of: (a) dispersing a surfactant, and coating thesurfactant with fine powder having a diameter from 0.1 to 500 microns,in a mixer wherein conditions of the mixer include (i) from about 2 toabout 50 seconds of mean residence time, (ii) from about 4 to about 25m/s of tip speed, and (iii) from about 0.15 to about 7 kj/kg of energycondition, wherein the first agglomerates are formed; (b) thoroughlymixing the first agglomerates in a second mixer, said mixer beingprovided with choppers to break up undesirable oversized agglomerates,wherein conditions of the mixer include (i) from about 0.5 to about 15minutes of mean residence time and (ii) from about 0.15 to about 7 kj/kgof energy condition, wherein second agglomerates are formed; (c)spraying finely atomized liquid onto the second agglomerates in a mixerwhere in conditions of the mixer include (i) from about 0.2 to about 5seconds of mean residence time, (ii) from about 10 to about 30 m/s oftip speed, and (iii) from about 0.15 to about 5 kj/kg of energycondition; (d) optionally dispersing an aqueous or non-aqueous polymersolution with said surfactant in step (a); (e) optionally adding to step(c) excessive fine powder formed in step (a) and/or step (b); and (f)optionally subjecting resultant from step (c) to cooling and/or dryingstep which creates an internal recycle stream of powder, the internalrecycle stream of powder being added to step (a).
 2. A process accordingto claim 1 wherein said surfactant is selected from the group consistingof anionic surfactant, nonionic surfactant, cationic surfactant,zwitterionic, ampholytic and mixtures thereof.
 3. A proce ss accordingto claim 1 wherein said surfactant is selected from the group consistingof alkyl benzene sulfonates, alkyl alkoxy sulfates, alkyl ethoxylates,alkyl sulfates, coconut fatty alcohol sulfates and mixtures thereof. 4.A process according to claim 1 wherein the aqueous or non-aqueouspolymer solution is dispersed with said surfactant in step (a).
 5. Aprocess according to claim 1 wherein the fine powder is selected fromthe group consisting of soda ash, powdered sodium tripolyphosphate,hydrated tripolyphosphate, sodium sulphates, aluminosilicates,crystalline layered silicates, phosphates, precipitated silicates,polymers, carbonates, citrates, nitrilotriacetates, powderedsurfactantsand mixtures thereof.
 6. A process according to claim 1wherein the finely atomized liquid is selected from the group consistingof liquid silicates, anionic surfactants, cationic surfactants, aqueouspolymer solutions, non-aqueous polymer solutions, water and mixturesthereof.
 7. The process according to claim 1 wherein the excessive finepowder formed in step (a) and/or step (b) is added to step (c).
 8. Aprocess according to claim 1 wherein the resultant from step (c) issubjected to cooling and/or drying step, and the internal recycle streamof powder is added to step (a).